Pro hac vice, literally translates to "for this occasion", is a Latin legal term for a practice in common law to allow an attorney from another jurisdiction who is not licensed to practice law in a specific jurisdiction to participate as council of record on a single case basis. In this instance Jack McCoy is a member of the New York state bar and licensed to practice law in that state, but he is not a member of the Maryland state bar and thereby not licensed to practice law in Maryland which normally means he would not be allowed to act as an attorney in Maryland. However by granting a pro hac vice motion the judge is making an exception to allow McCoy to sit second chair and act as co-prosecutor in Dr. Janaway's case alongside ADA Danvers. When a pro hac vice motion is not requested by a judge it must be made by an attorney who is a member of that jurisdiction's bar, that attorney submits a motion to the judge on the case he/she is working to allow an attorney who is not a member of that state's bar to become a temporary member of the state bar just for that case. The visiting attorney is usually required to submit documentation that he/she is a current member of the bar in the state he/she normally practices law in and holds a current, valid law license. Pro hac vice motions are actually not very common, and while all 50 states in the United States have some form of a pro hac vice statute, they intend for pro hac vice admission to be used on a sparing and occasional basis.